deal with resources in unknown states

[BenTheElder]

I recently found that the Kubernetes boskos instances had projects wedged in "other" state from the metrics, which appears to be kubernetes-sigs/image-builder#1534

We should guard against mistaken usage like this.

Ideas:

1. Boskos API could offer a setting to return an error to clients that set state not in a supplied list (configurable)
2. Boskos API could serve a warning header, and boskosctl could become aware of this (... more complex, may not catch as many other clients)
3. Reaper (or some other controller) could have a mode to force resources to dirty state when it encounters them in an unknown state. For now I'm planning to manually do this one-off.

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/lifecycle stale

[BenTheElder]

/lifecycle frozen